Environment-friendly chemical reduction gold liquid and process thereof

The invention relates to the technical field of semiconductor manufacturing, in particular to environment-friendly chemical reduction gold liquid and a process thereof.The environment-friendly chemical reduction gold liquid is prepared from gold thiocyanate serving as a gold source and ammonium thiocyanate and an auxiliary reducing agent which are matched to serve as a composite reducing agent; the concentration of the gold thiocyanate salt in the chemical reduction gold liquid is 1.5 g/L-2. 5 g/L; the concentration of ammonium thiocyanate in the chemical reduction gold liquid is 10 g/L-20 g/L; and a composite coordination agent, a pH buffer agent and an auxiliary agent. By the adoption of the chemical reduction gold liquid, a plating layer has good brightness and uniformity and good microtopography, the phenomenon that due to excessive corrosion of gold changing liquid medicine, severe nickel corrosion is generated, and consequently after welding, parts fall off or the interface of soldering tin and a weldin